Theoretical investigation of laser-sustained argon plasmas

Abstract

A theoretical model has been developed for laser-sustained argon plasmas in a forced convective axisymmetric pipe flow. The two-dimensional model based on Navier–Stokes equations was solved using a finite difference algorithm, and included geometric optics, temperature-dependent thermodynamic, transport, and optical properties, as well as radiation-induced thermal conductivity. The results showed good agreement with existing experimental data on temperature distribution, shape, and size of the plasma. The calculated velocity distribution revealed the complexity of the flow field and indicated that the constant axial mass flux (product of axial velocity and density) assumption adopted by existing one-dimensional and semi-two-dimensional models is not adequate. The radiation transfer was found to have a significant influence on the predicted temperature distribution and peak temperature of laser-sustained plasmas.